全文获取类型
收费全文 | 6310篇 |
免费 | 459篇 |
国内免费 | 57篇 |
专业分类
耳鼻咽喉 | 26篇 |
儿科学 | 137篇 |
妇产科学 | 120篇 |
基础医学 | 954篇 |
口腔科学 | 103篇 |
临床医学 | 586篇 |
内科学 | 1617篇 |
皮肤病学 | 103篇 |
神经病学 | 739篇 |
特种医学 | 167篇 |
外科学 | 630篇 |
综合类 | 14篇 |
一般理论 | 1篇 |
预防医学 | 396篇 |
眼科学 | 65篇 |
药学 | 497篇 |
中国医学 | 13篇 |
肿瘤学 | 658篇 |
出版年
2024年 | 6篇 |
2023年 | 66篇 |
2022年 | 158篇 |
2021年 | 289篇 |
2020年 | 148篇 |
2019年 | 186篇 |
2018年 | 245篇 |
2017年 | 178篇 |
2016年 | 191篇 |
2015年 | 248篇 |
2014年 | 281篇 |
2013年 | 325篇 |
2012年 | 540篇 |
2011年 | 556篇 |
2010年 | 277篇 |
2009年 | 248篇 |
2008年 | 441篇 |
2007年 | 454篇 |
2006年 | 388篇 |
2005年 | 394篇 |
2004年 | 334篇 |
2003年 | 342篇 |
2002年 | 253篇 |
2001年 | 37篇 |
2000年 | 20篇 |
1999年 | 31篇 |
1998年 | 31篇 |
1997年 | 30篇 |
1996年 | 23篇 |
1995年 | 15篇 |
1994年 | 15篇 |
1993年 | 15篇 |
1992年 | 7篇 |
1991年 | 14篇 |
1990年 | 6篇 |
1989年 | 5篇 |
1988年 | 5篇 |
1986年 | 2篇 |
1985年 | 5篇 |
1984年 | 3篇 |
1983年 | 1篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1974年 | 1篇 |
1971年 | 1篇 |
1970年 | 2篇 |
1969年 | 2篇 |
1918年 | 1篇 |
排序方式: 共有6826条查询结果,搜索用时 0 毫秒
11.
Mario Zama Simona Gallo Luigino Santecchia Ettore Bertozzi Antonio Zaccara Alessandro Trucchi Antonella Nahom Pietro Bagolan Cosmoferruccio De Stefano 《British journal of plastic surgery》2004,57(8):749-753
Omphalocele is the most common congenital defect of the abdominal wall. Mortality rate is between 20 and 70% and early closure of the abdominal wall, within 10 days of life, is vital to the successful outcome of the surgical treatment. The authors describe the use of two bipedicled flaps of abdominal skin to correct the defect of the midline as soon as the reduction of all viscera has been accomplished. 相似文献
12.
Flavio Masi Benedetta Leggio Giulio Nanni Simona Scheggi M Graziella De Montis Alessandro Tagliamonte Silvia Grappi Carla Gambarana 《Neuropsychopharmacology》2003,28(4):683-693
Long-term acetyl-L-carnitine (ALCAR) administration prevents the development of escape deficit produced by acute exposure to unavoidable stress. However, it does not revert the escape deficit sustained by chronic stress exposure. Rats exposed to chronic stress show a low dopamine (DA) output in the nucleus accumbens shell (NAcS) and do not acquire an appetitive behavior sustained by the earning of vanilla sugar (VS) made contingent on the choice of one of the two divergent arms of a Y-maze (VS-sustained appetitive behavior, VAB), while control rats consistently do. The present study shows that ALCAR treatment in rats exposed to a 7-day stress protocol prevented a decrease in DA output in the NAcS and medial prefrontal cortex (mPFC) of rats, and that it strengthened the DA response to VS consummation in the same two areas. Moreover, rats treated with long-term ALCAR or exposed to chronic stress while treated with ALCAR acquired VAB as efficiently as control rats. Moreover, VAB acquisition in stressed rats treated with ALCAR coincided with the reversal of the deficits in escape and in dopaminergic transmission in the NAcS. Thus, repeated ALCAR treatment preserved the DA response to VS in chronically stressed rats and this effect appeared to be predictive of the rat's competence to acquire VAB. 相似文献
13.
Although central serous retinopathy is considered a "benign" condition, it is associated in healed forms with frequent and troublesome impairment of visual function. The abnormalities are even more severe after diffuse retinal pigment epitheliopathy. Since Snellen visual acuity testing is a relatively imprecise index of visual function, it does not enable the subtle visual disturbances experienced by these patients to be fully appreciated. The authors evaluated visual function disorders by static automated perimetry and contrast sensitivity in 30 patients with healed central serous retinopathy and in five patients with diffuse epitheliopathy at a cicatricial stage. The results of this study are examined and discussed. 相似文献
14.
Daniela Concolino Simona Sestito Francesca Falvo Giusy Romano Miriam Ceravolo Elisa Anastasio Licia Pensabene Elisa A. Colombo Lidia Larizza 《European journal of medical genetics》2019,62(1):73-76
Clericuzio-type poikiloderma with neutropenia is a well-defined nosological entity, but despite a remarkable number of clinical reports, no long term follow-up data has been presented to date regarding patients with this rare condition.Here we describe the results of clinical follow-up of three siblings, one male (Patient 1) and two females (Patients 2 and 3), subsequent to their first clinical and then molecular diagnosis of Clericuzio-type poikiloderma with neutropenia syndrome due to mutation of USB1gene. Patient 1 always expressed the most severe phenotype, while patients 2 and 3 showed an intermediate and mild phenotype, respectively, as observed since their first clinical evaluation. None of the patients developed skin cancer and/or myelodysplastic disorders considering the peripheral haematological findings. Lens opacity, never reported before, was found in two of the three patients.The long term follow-up observations confirm the stability over time of the pronounced intra-familial heterogeneity of clinical manifestations observed prior to and upon molecular diagnosis. We conclude that prolonged follow-up is an adjunct tool to monitor intra-familial variability of PN clinical spectrum which may favour surveillance of more serious complications of the disease among siblings, when a patient-specific clinical expressivity is present. 相似文献
15.
Licastro F Grimaldi LM Bonafè M Martina C Olivieri F Cavallone L Giovanietti S Masliah E Franceschi C 《Neurobiology of aging》2003,24(7):921-926
Two different polymorphic regions of the interleukin-6 (IL-6) gene were investigated in patients with Alzheimer's disease (AD) and non-demented controls. The -174 C allele in the promoter region of IL-6 gene was over-represented in AD patients compared to controls and significantly increased the risk of AD. Moreover, the -174 CC genotype was associated with a high risk of the disease in women. The D allele of a variable number of tandem repeat (VNTR) was in strong linkage disequilibrium with the -174 C allele and slightly increased AD risk. On the other hand, the frequency of the VNTR C allele was decreased in patients with AD and was negatively associated with the risk of developing AD. Both the -174 CC and VNTR DD genotypes were also associated with increased IL-6 levels in the blood and brain from AD. These findings suggest that IL-6 may play a multifaceted role in AD by affecting the turnover of the cytokine. 相似文献
16.
Parazzini Fabio; Tozzi Luca; Chatenoud Liliane; Restelli Simona; Luchini Laura; Vecchia Carlo La 《Human reproduction (Oxford, England)》1994,9(10):1950-1953
The objective of this study was to assess the association betweenalcohol drinking before and during pregnancy and the risk ofspontaneous abortion using data from a case-control study conductedin Milan, Italy. A total of 462 women (median age 30 years)were admitted for spontaneous abortion (within the 12th weekof gestation) to a network of obstetrics departments in thegreater Milan area. Of these, 148 (32%) were between the fourthand the eighth week of gestation and 314 (68%) between the ninthand the 12th week. A control group was made up of 814 women(median age 29 years) who gave birth at term (>37 weeks gestation)to healthy infants (Apgar 5th minute 8, weight 3000 g) on randomlyselected days at the same hospitals where cases had been identified.A total of 212 cases (46%) and 355 controls (47%) reported alcoholdrinking before conception. Considering non-drinkers as thereference category, the relative risks (RR) of spontaneous abortionwere 1.2 (95% confidence interval (CI), 0.91.6] and 0.8(95% CI, 0.61.1), respectively, in drinkers of one toseven and more than seven drinks per week before conception.No association emerged between the duration of alcohol drinkingand the risk of spontaneous abortion. A total of 166 cases (35.9%)and 263 (32.3%) controls reported any alcohol drinking duringthe first trimester of pregnancy. The corresponding relativerisk was 1.1 (95% CI, 0.91.4) and no relationship emergedbetween the number of drinks per week and the risk of abortion.Likewise, maternal wine and beer drinking in the first trimesterof pregnancy was not associated with the risk of spontaneousabortion. Evidence available from this and previous studies,although partially controversial, indicates that moderate (oneor two drinks per day) alcohol consumption does not increasemarkedly the risk of miscarriage. 相似文献
17.
Vitale M Della Chiesa M Carlomagno S Romagnani C Thiel A Moretta L Moretta A 《European journal of immunology》2004,34(6):1715-1722
The encounter of NK cells with dendritic cells (DC) undergoing maturation may result in the induction of NK cell proliferation. Whether such proliferation involves most NK cells or just a subset has yet to be determined. In the present study we analyzed the nature of such proliferating NK cells by combining carboxyfluorescein succinimidyl ester staining and double-fluorescence cytofluorimetric analysis. Freshly isolated peripheral blood NK cells cultured with LPS and immature DC underwent proliferation; however, proliferating cells were confined to a minor NK cell subset. This subset is characterized by the CD56(bright)CD16(-)NKG2A(+)KIR(-) surface phenotype (KIR, killer Ig-like receptor). This was further confirmed by the fact that, after cell sorting, only the CD56(bright) NK cells were able to proliferate in response to the DC stimulus, whereas the CD56(dull) were not. We also provide evidence that the CD56(bright) subset is the main source of IFN-gamma-producing NK cells, upon interaction with DC. The CD56(bright)CD16(-) NK cells express a panel of surface molecules including CD62L, CCR7 and CXCR3 that may allow their homing either to secondary lymphoid compartments or to inflamed tissues. This implies that, in vivo, the interactions between DC undergoing maturation and CD56(bright) NK cells may occur in different tissues and have different functional implications. 相似文献
18.
Adrian Bot Simona Bot Adolfo García-Sastre Constantin Bona 《Clinical & developmental immunology》1998,5(3):197-210
Neonate organisms display an intrinsic disability to mount effective immune responses to
infectious agents or conventional vaccines. Whereas low. doses of antigens trigger a suboptimal
response, higher doses are frequently associated with tolerance induction. We investigated the
ability of a plasmid-expressing nucleoprotein of influenza virus to prime a specific cellular
immune response when administered to newborn mice. We found that persistent exposure to
antigen following plasmid inoculation of neonates leads to a vigorous priming of specific CTLs
rather than tolerance induction. The CTLs were cross-reactive against multiple strains of type A
influenza viruses and produced IFNγ but no IL-4. The immunity triggered by plasmid
inoculation of neonates was protective in terms of pulmonary virus clearance as well as survival
rate following lethal challenge with influenza virus. Whereas the persistence of the plasmid at the
site of injection was readily demonstrable in adult mice at 3 months after inoculation, mice
immunized as newborns displayed no plasmid at 3 months and very little at 1 month after
injection. Thus, DNA-based immunization of neonates may prove an effective and safe
vaccination strategy for induction of cellular immunity against microbes that cause serious
infectious diseases in the early period of life. 相似文献
19.
Zauli D Contestabile S Grassi A Bortolotti R Ballardini G Bianchi FB 《The Journal of allergy and clinical immunology》2002,110(3):538-9; author reply 539
20.
Paglia F Dionisi S Minisola S 《The New England journal of medicine》2002,346(22):1748-9; author reply 1748-9